Given,
The initial inside diameter of the pipe, d₁=4.50 cm=0.045 m
The initial speed of the water, v₁=12.5 m/s
The diameter of the pipe at a later position, d₂=6.25 cm=0.065 m
From the continuity equation,

Where A₁ is the area of the cross-section at the initial position, A₂ is the area of the cross-section of the pipe at a later position, and v₂ is the flow rate of the water at the later position.
On substituting the known values,

Thus, the flow rate of the water at the later position is 5.99 m/s
Answer:
Sundial is an instrument showing the time by the shadow of a pointer cast by the sun on to a plate marked with the hours of the day.
For this problem to be solved, we make use of the de Broglie formula which is written below as follows:
λ = h/mv
where h is 6.626×10⁻³⁴ J·s
9.74 × 10⁻³⁵ m = 6.626×10⁻³⁴ J·s/ (m)(46.9 m/s)
Solving for m,
<em>m = 0.145kg</em>